1. Field of the Invention
The present invention relates generally to semiconductor fabrication systems, and, more particularly, to semiconductor wafer fabrication systems including manufacturing execution systems.
2. Description of Related Art
Integrated circuits are typically formed by processing several semiconductor wafers as a group or xe2x80x9clotxe2x80x9d through a series of wafer fabrication process tools (hereafter, xe2x80x9cprocess toolsxe2x80x9d). Each process tool typically performs a single wafer fabrication operation upon the semiconductor wafers. The integrated circuits formed in this manner are substantially identical to one another. Following wafer fabrication, the integrated circuits are typically subjected to functional testing, and then separated to form individual integrated circuits called xe2x80x9cchipsxe2x80x9d or xe2x80x9cdie.xe2x80x9d Fully functional die are typically packaged and sold as individual units.
Driven by fierce competition, semiconductor fabrication facilities are economically compelled to ensure efficient scheduling and utilization of process tools. To increase equipment productivity, many modern semiconductor wafer fabrication systems include a centralized manufacturing execution system (MES). Functions performed by a typical MES may include: work in process (WIP) tracking, resource allocation and status, operations scheduling, quality data collection, and process control. A MES may also function as a central depository for data collection and distribution. For instance, a MES can, in real-time, dynamically collect, combine and express the data of raw materials, finished products, semi-finished products, machines, time, costs, etc., and can trace and control each manufacturing process.
A typical MES includes a single database for storing information used to automatically monitor and control process tools. For example, in a semiconductor wafer fabrication system including a MES, the single database of the MES may be a xe2x80x9cbasicxe2x80x9d database including xe2x80x9cbasicxe2x80x9d records, wherein each basic record includes information to be used by a process tool to automatically execute a process. The MES may compare operation data received from the process tool to each of the basic records, and allow the process to be executed only if the operation data matches a basic record.
A problem arises in the above described semiconductor wafer fabrication system in that in some situations, the MES may deny execution of a process even though the operation data matches a basic record in the basic database. The MES may deny execution of a process, for example, when tool performance decreases or when a defect is found in the wafer process. Because the tool performance decreases, in such situations, the problem is typically resolved by removing the basic record which matched the operation data, and later restoring the basic record to maintain the basic database. A substantial amount of time can be expended in removing and restoring basic records.
A need thus exists in the prior art to eliminate manually removing, and later restoring, records in an MES database in order to allow a process to be automatically carried out within a process tool.
The present invention addresses these needs by providing a semiconductor MES including a memory module, a comparing module, and an outputting module. The memory module stores a basic database and a recipe distribution management (RDM) database. The basic database includes multiple basic records, and the RDM database includes multiple RDM records.
The comparing module compares operation data, received from a manufacturing machine, to each of the basic records, and secondarily to each of the RDM records, to determine if the operation data matches at least one of the basic records and the RDM records. The outputting module outputs a limiting signal to the manufacturing machine if the operation data matches at least one of the RDM records. The limiting signal prevents the manufacturing machine from executing a process corresponding to the operation data.
The outputting module may also output a first alarm signal to the manufacturing machine, and a second alarm signal to the user interface, if the operation data does not match at least one of the basic records and the RDM records.
The semiconductor MES may also embody methods for adding new RDM records to the RDM database, editing RDM records in the RDM database, and/or deleting RDM records from the RDM database.
Any feature or combination of features described herein are included within the scope of the present invention provided that the features included in any such combination are not mutually inconsistent as will be apparent from the context, this specification, and the knowledge of one of ordinary skill in the art. Additional advantages and aspects of the present invention are apparent in the following detailed description and claims.